Manufacture of sirup



Patented Nov. 4, 1941 v UNITED- STATES" PATENT OFFICE MANUFACTURE OF SIRUP Ernest E. Pittman and Robert Roger Bottoms,

Louisville, Ky., assignors to The Girdler Corporation, Louisville, Ky., a corporation of Delaware No Drawing. Application December so, 1938,

Serial No. 248,582

6 Claims. ,(Cl. 99- 142) This application is a continuation in part of to the fact that the undesirable ingredients are our copending application Serial No. 244,206,1iled present in large amount and could not besatis- December 6, 1938. The invention relates to the factorily removed by the use of previous types manufacture of sirup from sugar cane, sorghum, of treatment such as lime, sulphitation, phosm'aple sap, and other sugar-bearing materials, '5 .phoric acid, etc. and to the production of an improved type of Extensive milling to insure extraction of all of sirup. Heretofore in the manufacture 'of sirup, the sucrose has at the same time increased the lack of uniformity in quality and/or density of amount of fine solidsin suspension and increased the product has been a major problem in the the amount of non-sugars extracted. As certain industry. Variations in varieties and conditions -10 of the undesirable ingredients could not be satisof the sugar cane or other type of sugar-bearing factorily removed from the cane juice by prior materials, incomplete removal ofundesirable inprocesses, it has not been feasible to carry the gredients from the sugar juices, and inherent milling operations on the cane as far as the limitations in the type of manufacturing procoperator might otherwise desire. esses employed, have all contributed to-the prob- This invention has as an object the provision lems confronting the manufacturer. of a process for manufacturing sirup in which For example, in a common variety of sugar the above disadvantages of present processes are cane, many undesired constituents such as ash, eliminated or substantially reduced, and the proteins, nucleins, proteoses, amides, amido manufacture of the sirup simplified.' acids, other organic acids, gums and pectins, 2 As a further object the invention provides a fiber particles, fats and waxes, chlorophyll and process of manufacturing sugar cane sirup in other coloring materials such as anthocyanln, "which the concentration may be efiected in mulsaccharetin, water soluble polyphenols and tantiple-efiect evaporators of either the vacuum or nin-like compounds, and earthy matter are pressure type. usually found. These collectively are herein- As a further object, the invention provides a after referred to as non-sugar ingredients or unprocess for treating certain sugar-bearing matedesirable ingredients. Ingredients of this charrials which heretofore could not be satisfactorily acter have various deleterious effects on the final used for the manufacture of sirup. product, depending on the amount and kind of Another important object of the invention is such ingredients left in in the process of manuthe productionof a new type of sirup having new facture. The sirup may have undesirable color and distinctive.characteristics, including lighter and taste characteristics, variations in viscosity, color. better roma. milder flav a d a s n of may generate gases after standing, may form turbidity and nitrogenous mattercloudy precipitateson standing, or may change Other objects and advantages will become in color after a period of time, all of which af- '35 more apparent as the description proceeds. feet the marketing of the product. As an important feature of the present inven- The open type of evaporators heretofore comtion the removal of a very large proportion of monly used for the concentration of the sugar the non-sugar ingredients is effected in a very juices, has been. made necessary since known simple and inexpensive manner before there has methods of clarification of the juices have re- 40 been any substantial concentration of the juice, quired the substantially continuous or repeated instead of during the concentration. Thus low skimming off of the scum during the progressive grade canes and too extensive milling no longer heating and concentration of the juices. In this present a serious problem, and the concentration type of evaporators there is the ever present danis more effectively carried out,- because of the abger of scorching the sirup or altering the flavor 345 sence of the undesirable constituents from the or color, due to any failure to accurately control solution being concentrated.

the heating; the operation is costly, due to the In the manufacture of sirup from sugar cane/ large expenditure required for heat, time and the following procedure is given as an example, labor, and the removal of non-sugar ingredients although the invention is not limited to the dehas been effective to y a ry limited extent. tails given, or to the use solely of sugar cane.

Certain canes, such for example as frozen The juice resulting from the crushing of the canes, canes which are low in pH, canes grown sugar cane in the mills is directed to a "suitable in certain types of soil, and canes of unusual biostorage vat, and bentonite slurry is added therelogical characteristics, such as certain of the to. The bentonite used forms a stable colloidal Java varieties, could not be used heretofore, due suspension in water and the particles will remain in suspension for an indefinite period of time. The bentonite is neither acid nor alkaline in character. As a result of this step there is formed an agglomerate of bentonite and undesirable constituents found in the cane juice, including those which are in solution as well as those in suspension. This agglomerate of bentonite and undesirable constituents of the Juice forms in a short period of time, and may be facilitated by thorough mixing or agitating, for instance by air or by, mechanical means.

A satisfactory agglomeration will occur if the amount of bentonite by dry weight is about 96 of 1% of the weight of the Brix solids in the juice. An excess of bentonite does not harm, and neither does it give any benefit. Too small an amount of bentonite may not give adequate purification.

Preferably we use the bentonite in the form of slurry having about one part bentonite by weight to fifteen parts of water, and which may have been aged for a period of time.

Raw untreated juice is always of acid character. We prefer to treat the raw juice at the same pH at which it is found, but if desired, adjustment of the pH can be made at this or any subsequent stage of the processing. Such adjustment should not be to an extent which will make the juice alkaline or even neutral, because, as is well known in this art, the presence of acids facilitates or accelerates the inversion of sucrose to the desired glucose of sirup.

Following the mixing of the Juice and bentonite in the proportion described, the mixture is either heated in the same vessel or delivered to a separating means through any suitable heating means with or without mechanical or other agitation. The heating is preferably to about 190 F., but may be anywhere above, short of the boiling point. It is not necessary to continue the heating for any length of time, and the heat may be shut ofl as soon as the desired temperature has been reached. The heating fiocculates the agglomerate and facilitates separation either in the: same vessel or in a separate chamber.

The mixing and heating may be by batches or as a continuous process, Proportioning pumps may deliver the slurry and Juice through a mixing device, thence through a heating coil or other means, and thence to the separating means.

We have found that the so called open defecators are well adapted as a separating means, since a relatively short period. of time is needed for separation of the agglomerate from the clarified juice; and no additional heat is required at this stage of operation. The agglomerate is usually of a light green color, and contains the bentonite and nitrogenous material, waxes and gums, some of the coloring matter such as chlorophyll, bits of cellulose and other suspended matter, and the like, and will rise to the top of the body of juice as a comparatively thick scum, thus giving gravity separation.

The intimate mixing of the slurry and raw cane juice, together with the agitation occurring in the heaters, enhances the formation of the agglomerate, and the gravity separation taking place in a .defecator enhances, the separation of the two types of material, since the scum rising toward the top of the liquid bath tends to raise and to filter out of the juice those bits of suspended solids and colloidal ingredients which may actually be heavier than or of about the same specific gravity as the juice itself.

Any suitable method or means for separation of the agglomerate or scumfrom the clarified liquid may be employed, and if open defecators are used, the clarified liquid may be drained from the bottom of the defecation tank and the scum may be given'a suitable later treatment such as passage through a filter press or the like for recovery of any sugar-containing Juice remaining therein, or for recovery of any other ingredients thereof. Although separation of juice and agglomerate in a defecator is preferable, we may effect the separation in a filter press or any other type of filtering means, or in a centrifuge.

Since the agglomerate resulting from the rapid and substantially completeremoval of undesired constituents from the juice is formed during the mixing of bentonite and raw juice, and is completed during the heating treatment, it is possible to remove substantially all of the agglomerated materials at one time. Since the removal of undesired constituents is effected before concentration, it becomes possible to use closed multiple effect vacuum or pressure evaporators in the concentration of the sirup, which has not heretofore been practical except in the case of sulphitation sirup.

During this concentration to about 50 Brix, a certain cloudiness or turbidity may develop. The sirup should be permitted to stand for about 24 hours, and the solids will settle out without the need for filtering. The sirup from the evaporators, and after settling out of solids in suspension, may then be directed to any suitable final concentrating apparatus in which inversion of sucrose is continued, due to the action of heat and the contained non-volatile organic acids. We prefer to direct the concentrated sirup into a second evaporator means such as an open boiling pan in which the sirup may be heated to an appropriately high temperature until sufilcient concentration and resulting inversion has taken place, and until the sirup has the desired density. In this phase of operation the sirup will come to a final content of about 70% solids, and will have a light color and a distinctive, desirable flavor. These characteristics are though to be due primarily to efficient defecation resulting in substantially complete removal of such ingredients as coloring matter, nitrogenous matter, waxes, gums and the like, before concentration.

In the event that it is desired to direct the heated Juices to the evaporators before complete removal of undesired constituents has taken place, it is possible to remove any small amount of undesired constituents rising tothe surface of the concentrated sirup'during the final evaporation stage of operation, thus insur-'- ing complete removal of undesired constituents in two stages, in contrast with present day practices of removing the scum gradually as it is formed. From the final stage of evaporation, the sirup may be directly packaged after proper temperature adjustment.

It is found that the sirup made as above described will be substantially free of all undesirable ingredients heretofore mentioned, and will have a comparatively light color and an improved flavor, when compared with commercial sirups made by processes known at present.

Having thus described our invention what we claim as new and desire to secure by Letters Patent is:

1. The method of producing light color table sirup, including the steps of mixing colloidal bentonite capable of dispersion in water and forming a relatively stable colloidal suspension therein, with a sugar-containing juice having substantially its original pH and containing a sufiicient quantity of non-sugars to coagulate a stable suspension of colloidal bentonite, thereby rapidly forming a coagulum of bentonite and substantially all of the color forming non-sugar ingredients of the juice, separating said c0agulum from the clarified juice before there has been any substantial concentration of the juice, and thereafter concentrating the juice under sucrose inverting conditions to form the light color sirup.

2. The method of producing light color tabl sirup, including the steps of mixing colloidal bentonite capable of dispersion in water and forming.

a relatively stable colloidal suspension therein, with a sugar-containing juice having substantially its original pH and containing a sufficient quantity of non-sugars to coagulate a stable suspension of colloidal bentonite, heating the mixture to about 190 F., thereby rapidly forming a coagulum of bentonite and substantially all-of the color forming non-sugar ingredients of the juice, separating said coagulum from the clarified juice before there has been any substantial concentration of the juice, and thereafter concentrating the juice under sucrose inverting conditions to form the light color sirup.

3. The method of producing light color table sirup, including the steps of mixing colloidal bentonite capable of dispersion in water and forming a relatively stable colloidal suspension there-l oration, the juice under sucrose inverting conditions to form the light color sirup.

5. The method of producing light color table sirup, including the steps of mixing colloidal bentonite capable of dispersion in water and forming a relatively stable colloidal suspension therein, with a sugar-containing juice having substantially its original pH and containing a suflicient quantity of non-sugars-to coagulate a stable suspension of colloidal bentonite, the bentonite being.

about 1 6 of 1% of the soluble solids of the juice, thereby rapidly forming a coagulum of bentonite and substantially all of the color forming nonsugar ingredients of the juice, separating said coagulum from the clarified juice before there has been any substantial concentration of the juice, and thereafter concentrating the juice under sucrose inverting conditions to form the light color sirup.

6. The method of producing light color table sirup, including the steps of mixing a colloidal bentonite capable of dispersion in water and forming a relatively stable colloidal suspension therein, with a sugar-containing juice having substantially its original pH and containing a sufficient quantity of non-sugars to coagulate a stable suspensionof colloidal bentonite, the bentonite being about 1% of 1% of the soluble solids of the juice, heating the mixtur to about 190 F., thereby rapidly forming a t hick scum of bentonite and substantially all of the color forming non-sugar ingredients of the juice, separating said scum in an open defecator from the clarified juice before there has been any substantial concentration of the juice, and thereafter concentrating, by multiple-effect evaporation, the juice under sucrose inverting conditions to form the light color sirup.

ERNEST E. PITTMAN.

ROBERT ROGER BOTTOMS. 

